Amtrak's long-delayed Acela Express trains along the Northeast Corridor won't be rolling for the public until Dec. 11--except for a few surprise runs for passengers expecting a Metroliner ride. But crews running dress rehearsals are now taking aboard fake customers, namely Amtrak executives and the odd journalist.

They agreed to let me--one of the odd journalists who happens to be the daughter of a former freight conductor--ride behind the bullet-shape locomotive on a recent D.C.-to-Boston test run. I regretfully got off in New York and, a few hours later, rode a Metroliner home.

Amtrak is betting that its customers, both old and new, will be willing to pay about $20 more to ride a lot more comfortably and a little faster (the Acela Express will shave 15 to 30 minutes off the D.C.-New York leg).

Train buffs and the mechanically inclined might be interested in the advanced technology produced in a venture between Canadian and French companies: the tilt-wheel mechanism that takes curves and bumps more gracefully for a smoother ride, the electric propulsion system that generates 12,500 hp. The tracks of the Northeast Corridor, built centuries ago along river banks and cow paths, slow the Acela's potential. But on test runs along straight stretches, locomotive engineers have revved the train to 170 mph.

But here's the scoop for travelers simply interested in the ride: It's a whole lot nicer.

Upon boarding you're hit with a wonderful new-car smell, although a few hot dogs left under the seats will probably erase that advantage soon enough.

Ironically, the Acela's best feature is retro: giant windows that hark back to the days when train travel was elegant, designed to be fun. Sometimes the windows frame freight yards and car lots. But I got a spectacular autumn leaf experience as the train crossed meadows and fields, and the broad banks of the Gunpowder, Bush and Susquehanna rivers, all flowing to the Chesapeake.

Like McDonald's, which won't admit to selling "small" fries, the Acela Express doesn't call either of its classes "coach." The choices are business and first.

The latter might be the way to go if you're holding a meeting on board, need a surprisingly good meal or can drink enough booze to make up the $74 cost difference (food and drinks are free in first class).

Otherwise, business class is perfectly comfortable--a clean, well-lighted place. The seats recline dramatically. Forty-two inches of space stretches between each seat-- more leg room than typically found on a first-class plane seat.

The cafe car food is advertised as more upscale, although that seems true mostly in comparison with the Metroliner. Bread products just don't take well to microwaves: That axiom was proved by the egg-and-cheese breakfast sandwich I ate. The omelets, pancakes and fruit platters in first class, though, were good enough to be enjoyed even as a second breakfast moments after dining in the cafe car.

And in fairness, the cafe car has made vast improvements in at least one major food group: The beer is available on tap.